Summary:

The degradation of the Odra river bed is observed mainly below each last barrage of the channelized river sector Koźle - Wrocław. The mean river bed level is decreasing of some 4-8 cm yearly, causing the corresponding drop so of water surface in the river as of the ground water level in the valley. This degradation causes great problems so for navigation, as for agriculture and environment. The construction of successives last barrages Wrocław (1897), Rędzin (1922) and Brzeg Dolny (1958) had only a temporary effect. Below each of these barrages the river bed erosion continued, concerning a river reach of some 50-60 km. In 1994 Parzonka has proposed the conception of the "feeding" of the Odra just below the new barrage Malczyce (km 300,0), entering in action probably in 2012. The ad-ministration has decided in 2008, that this barrage can enter in work only after the accomplishment of important restoration works, taking in account the needs of environment, of navigation and agriculture and of the human population. The programme of restoration works provides two steps:
- Step I: the elevation of the Odra bed level on the sector Malczyce-Ścinawa (km 300 - km 335) minimum by the half on the eroded height.
- Step II: the feeding of the Odra just below the barrage Malczyce on the length of some 4-5 km, after each flood causing local river bed erosion.